Project light through shape, text or symbol to appear in cloud or mist
You could either model your batman logo or get one from the internet in SVG file format and use it as an actual "geometry stencil" in your scene to block out light coming from a projector line.
If you prefer you may also use an image texture as alpha map for your stencil

Just make sure your spot light is strong enough to make a visible influence and the size of the lamp is small enough so the shadows don't become too blurry, otherwise it may be difficult to make out the symbol



EDIT

For the materials simply use a Volume Scatter shader connected to the Volume socket of the Material Output. For the red volume use a very low density like 0.1 or less, for the blue volume receiving the symbol a higher density is acceptable like 1.0.

For a more physically accurate version mix a Volume Scatter and a Volume Absorption nodes using the Mix Shader node